Process of tempering metals and other materials



' Feb. 16;19z6. 1,573,784 J. W. VAN METER PROQSS 0F TEMPERING METALS AND OT'HER MATERIALS Filed June 9, 1922 vla CHLQR/NE COMP/M AIR v ing is a specilication.

Patented Feb. 16,' 1926.`

PATE-Nur "oFFlcn JAMES w. VAN METER, or SAN BAFAnn'cALIFonNiA.

:enocnss 'or rnnrnnrne METALS Annornnn MATERIALS.

Application mea Julie 9,

To all whom 'it may concern:

Be it known that I, JAMES W. VAN METER,

a citizen of the-United States, and resident of San Rafael, in the county of Marin, State of'California, have invented a new land useful Process of Tempering Metals line cyanides, the object of the invention being to provide an improved method by which steel or other material can be tem-- pered in a very short time, at minimum cost,

cles of zinc, iron, lead, arsenic, or other metal, and on salts of cyanide, especially 'sodium cyanide, and potassium cyanide, as hereinafter described and claimed.

Inpthe accompanying drawing y Fig. 1 is a diagram, partly 1n elevation, and partly in section, showing an internal combustion engine cylinder, arranged to be tempered on the'inside, in accordance lwith my improved tempering method.

Fig. 2 is a similar view, showing a body of metal in the act of being temperedbn the exterior in accordance with my -1m proved method.

Fig, 3 is a similar view, showing a plow plate being tempered on only one exterior surface in accordance with my method.'

My improved method is especially adapted for tem ering hollow bodles such as 1nternal combustion engine cylinders en the inside, and for tem ering metallic articles,

suchfor instance p ow plates, moldboards,

dies and the like on the working side, from the exterior, but may also be used for temV pering an article or body of metalor other material. throughout its entire extent..

In carryin out my improved method, .I provide a su cient charge or bod of vinert material which may consist pre erably of sawdust, which `contains some moisture,

bran or the; like, and mur the same inti-l mately with an initially inert material,

1922. semi no. 567,096.

such as lfor instance particles of iron, lead, zinc, arsenic, or other. metal, and also with salts of cyanide, such as sodium cyanide,.or potassium cyanide, or cyanides of `the alkaline earths, and also preferably with benzol or hydrocarbon oil to act as a binder and also as a combustible agent. p

Such material is generally used in about the following proportions l Sawdust, l pound; iron filings, 2 pounds;

sodium cyanide, 1A? pound; benzol or hydro- I carbon oil, 1/2 pound.

Assuming that the article to be tempered is the cylinder 1 of an internal' combustion engine, and that the same is to be tempered on the inside, to render the same exceedingly hard on its inner surface and thereby minimize wear or .enlargement of the cylinder bore by the piston, I lill such cylinder with a` charge of such material, asfindicated at 2, secure the head 2* on the cylinder, close the valve opening with a plug 2", and close the lower end of the cylinder with a suitable closure 3, vwhich is here shown as lsecurely held in place by means of hook bolts 4. An escape pipe 5,1ea'ds from the closure to the outer air ata suitable point or to a suitable vessel 'of `water-or other place where the fumes maybe absorbed or neutralized, and this pipe is provided with a' valve 6 to enable said pipe to be opened or closed to any desired extent vor at 'any time required as may be necessary to enable any desired pressure to be vattained inthe cylinder while the same is being tempered. l. I also provide a suitable quantity of a reaction causing agent, such as for instance, chlorine, which is here shown diagrammatically as contained under pressure vin a liquid state in a tank 7. Said tank has a valve 8 which may be opened or closedat will to control the passage of chlorine gas from the tank to the cylinder or other work through a tube 9 which is here shown as entering the lcylinder throi h a suitable stopper 10 which lli) I first keep the valves 6 and 12 closed and open the valve 8 to liberate chlorine gas which then passes through the pipe 9 to theV charge 2 in the engine cylinder., The chemical reaction of the chlorine on the metallic particles causes intense heat to be instantly developed, Without the aid of oxygen, and to Whichthe interior et 'the cylinder is ersposed, and at the same time such heat brings about the dissociation of the sodium cyanide, `thereby causing cya-negen to be liberated, Leaving the valve 6 closed, the valve 8 may be also closed when a sufdcient quantity of the chlorine has been used and the valve 12 opened to cause compressed air to also enter the cylinder and by appropriately manipulating the valve l2 the compressed air may be used to a sufficient extent to regulate'the temperature in the cylinder, to give the required degree oi hardness or temper to the inner surface oi" the cylinder,

When the tempering has been edected the valve o is then opened and compressed air employed to scavenge the cylinder and drive out the poisonousvt'umes which are conveyed through the pipe 5 to a suitable point, and are hence rendered innocuous, and danger to the operative is avoided.

Pressure and heat on the cyanide make it extremely eective in tempering the Work. Moreover, my improved method enables a material economy oi cyanide to be el'ected as avcomparatively small quantity of the cyanide is all that is required by my improved method for tempering a surface ot considerable area. All the cyanide is confined and liberated in the cylinder under pressure, and hencev its tempering edect is much more rapid than when it is used'in the open by the process heretofore employed, and moreover there is a'certain amount of case hardening or carburizing action.

Another advantage resulting trom the use of my improved process is that the interior surface ot the Worlr can be instantaneously heated to the required degree tor tempering such surface, and Without heating the body of the Work throughout, when this is desired, and thus the tempering is confined to the Wearing surface, Without being appreciably imparted to the remainder ot the body of the Work. When the Work is thus tempered only on one surface, the untempered portion o' thebody acts as a cushion behind such tempered surface or portion.

My .improved method can also with equal facility beemployed for tempering an object iromv the outside. in Fig. 2, l show a '.iurnace la in which the worlr l5 is embedded in a charge 16 ot the initially inert material, the chlorine being introduced through ai pipe l?, and the 'gases emitted through a tlue l.

l`llfhen it is desired to temper only one exterior surface or a metallic object, such.

7 as tor instance, a plouf iron, the Work 19,

shown in 3, is arranged with only one atraves surface in contact With the charge 2O of the initially inert material, l.the other surta-ces of the ivorlrbeing protected by a bed 2l of suitable material such as for instance a paste composed of powdered asbestos mixed With a suiiicient quantity of saturated solution ot salammoniac to render the same plastic.v

1While l have herein described a speciiic mode of carrying out my improved process,

would have it understood `that inodiiica- Y" tions may be made Within the scope oi' my invention as deiined in the appended claims.

ln the preparation of the charge to be acted upon by the chlorine, l have used salts of cyanide, and have also used cyanides of the alkaline earths. l may omit both et 'them from the charge, and supply cyanogen or other tempering agent from an independent source to the work, While the Work is in the heated condition resulting from its exposure to the heat genera ted by the chemical reaction of the chlorine or other reaction causing agent, on the metallic particles, or other initially inert material, and l do not limit myself in such particulars.

l. Method of tempering consisting in heating the Worli in a non-oxidizing atmosphere and subjecting the same to thc action of cyanogen.

2. Method of tempering, consisting in heating the Work in a non-oxidizing atmosphere and subjecting the same to thc action of cyanogen under pressure.

3. Method of tempering, consisting in heating the Work in a non-oXidizing atmosphere, excluding the same from the outcr` air, and subjecting the same to the action of cyanogen.

4. Method of tempering, consisting in heating the Work in a non-oxidizing atmosphere, excluding the same from the outer air, and subjecting'the same to the action of cyanogen under pressure. Y

5. Method of tempering, consisting in eX- posing the Work to heat generated by the chemical reaction of a reaction causing agent, on initially inert material, in the presence of salts of cyaniden o. Method of tempering, consisting in eX- posing the work to heat generated by the chemical reaction of a reaction causing agent on initially inert material in a nonoxidizing atmosphere in the presence of salts of cyanide, and regulating the temperature of the Work during the tempering thereof. y 7. Method of tempering, consisting in excluding the Work from-the outer air, and exposing the Worky to heat generated by the chemical reaction of a reaction causing agent on initially inert material in a nonozridizing atmosphere in the presence of salts of cyanide.

8. Method ot tempering, consisting in escluding the work from the outer-air, a`nd exposing the workto heat generated by the chemical reaction of a reaction causing agent on initially inert material in a non' 'oxidizing atmosphere in the presence of salts of cyanide and under pressure. Y

9. Method of tempering, consisting in exposing the worlg `to heat generated by the chemical reaction of a reaction causing agent on initially inert material in a nonoxidizing atmosphere in the presence of salts of 'cyanide and under pressure.

" v10. Method of tempering a hollow body consisting in ex osing vthe interior thereol to heat generate by the chemical-reactlon of a'reaction causing agentA on ini ially inert material in a non-oxidizing atmosphere .in the presence of salts of cyanide.

11. Method of tempering a hollow body, consisting in exposing the` interior thereof to heat generated by the chemical reaction of a reaction causing agent on initially l inert material in a non-oxidizing atmosphere in the presence of salts of cyanide and under pressure. v

12. Method of tempering a hollow body, consisting in vexposing the interior' thereof to heat generated by the chemical reaction of a reaction causing agent -on initially inert material in a non-oxidizing atmosphere in the presence of salts of cyanide andunder pressure and regulating the ltemperature3 of the heated interior surface by the application of a cooling medium thereto.

13. Method of tempering, consisting in ex! posing the Work to heat generated by the chemical reaction of a reaction causingl agent on initially inert material in a nonoxidizing atmosphere in the presence of-salts of cyanide.

14. Method of-tempering a surface of a body,`consisting in exposing such surface to heat 4generated by the chemical reaction-of a reaction causing agent on -initially inert material in a non-oxidizing atmosphere in the presence of' salts of cyanide, and protecting other surfaces of such body from such heat.

' 15. Method of tempering, consisting in exposing the workv to heat generated by the chemical reaction of a reaction causing agent, on* inert material, in the presence of an'alkaline cyanide; k

16. Method of tempering, consisting in exposing the work to heat generated by the chemical reaction -of a lreaction causing agent on initially inert material in a nonoxidizing atmospherem the presence of an alkalinel cyanide, and regulating the teming agent on initially inert materialV in a by exposing the workfto the heat generated by the chemical reaction of a reaction causing agent` on initially inert material in a' non-oxidizing atmosphere. and applying such tempering agent to the heated work.

In witness whereof I ax my ture.

` JAMES wyannn'rna'.

Vsigna- 

